Every day, about ten people die from unintentional drowning. Of these, two are children aged 14 or younger. Drowning ranks fifth among the leading causes of unintentional injury death in the United States.
From 2005-2009, there were an average of 3,533 fatal unintentional drowning (non-boating related) annually in the United States—about ten deaths per day. An additional 347 people died each year from drowning in boating-related incidents. About one in five people who die from drowning are children 14 and younger. For every child who dies from drowning, another five receive emergency department care for nonfatal submersion injuries. More than 50% of drowning victims treated in emergency departments (EDs) require hospitalization or transfer for further care (compared with a hospitalization rate of about 6% for all unintentional injuries). These nonfatal drowning injuries can cause severe brain damage that may result in long-term disabilities such as memory problems, learning disabilities, and permanent loss of basic functioning (e.g., permanent vegetative state).
Nearly 80% of people who die from drowning are male. Children ages 1 to 4 have the highest drowning rates. In 2009, among children 1 to 4 years old who died from an unintentional injury, more than 30% died from drowning. Among children ages 1 to 4, most drowning occurs in home swimming pools. Drowning is responsible for more deaths among children 1-4 than any other cause except congenital anomalies (birth defects). Among those 1-14, fatal drowning remains the second-leading cause of unintentional injury-related death behind motor vehicle crashes.
The main factors that affect drowning risk are lack of swimming ability, lack of barriers to prevent unsupervised water access, lack of close supervision while swimming, location, and failure to wear life jackets, alcohol use, and seizure disorders.
Drowning can happen quickly and quietly anywhere there is water (such as bathtubs, swimming pools, buckets), and even in the presence of lifeguards.
People of different ages drown in different locations. For example, most children ages 1-4 drown in home swimming pools. The percentage of drowning in natural water settings, including lakes, rivers and oceans, increases with age. More than half of fatal and nonfatal drowning among those 15 years and older (57% and 57% respectively) occurred in natural water settings.
There are generally three types of drowning monitoring systems, systems based on CCTV cameras, systems based on CCTV cameras with computer monitoring and automatic alarms and systems based on wristband tags with computer monitoring and automatic alarms. These systems detect objects that enter the pool but do not differentiate between swimming people and drowning people.
A drowning system based on CCTV cameras is a passive aid to the lifeguard that gives an underwater view via CCTV cameras. However it does not incorporate a detection system. This system basically gives a lifeguard additional underwater views.
The CCTV cameras with computer monitoring and automatic alarms system is essentially a computer aided detection system, that is not primarily a CCTV system and does not require a lifeguard dedicated to watch the TV monitor. The system monitors the swimming pool water and when it detects a person in potential difficulty (i.e. a static solid object of appropriate size and shape), it alerts the lifeguard via an LED monitor. The LED monitor visually flashes and produces an audible alarm. The lifeguard will be given a location on the LED screen and can also see the ‘casualty’ on the supervision workstation monitor. The computer continually monitors the pool assessing any potential problem.
Glare can be a potential problem with viewing monitors in bright environments for CCTV based systems. There are also cultural and religious issues with respect to the use of cameras in swimming pools in some countries which limit substantially their use in a big number of countries.
Wristbands tags are individual wristbands, about the size of a small wrist watch that are worn by users of a pool. Wristbands based monitoring systems detect wristbands that are outside set depth, movement and time parameters. If a bather (with wristband) approaches the preset parameters of the system, an alert via radio and/or ultrasonic is generated. Initially a small audio sound and flashing LED light will remind the bather to return to a safer location. If the bather does not respond appropriately, the system activates alarms on the receivers worn by the lifeguards.
Such a wristband has some drawbacks in terms of reliability some of which are as follows: It cannot be used in salt or sea water. This is a serious limitation since many new pools and water parks are being made with salt water. This means that this wristband will not reliably work in all water environments or even at the seaside. It requires line of sight between the receiver and the transmitter, so it may not work if there is an obstacle between the base-station and the child.